Luminescence energy and carrier lifetime as a function of applied biaxial strain in InGaN/GaN quantum-well structures

摘要

Photoluminescence (PL) and Time-resolved PL (TR-PL) are used to measure the luminescence energy and carrier lifetime of InGaN/GaN quantum well (QW) structures as a function of biaxial strain and excitation density. A blueshift of the transition energy and a decrease in the carrier lifetime reveal a field-dependent spatial electron-hole (e-h) wavefunction separation. This behavior is observed both under the application of tensile, biaxial strain, which directly affects the piezo-related field, and under increased excitation density, which effectively screens the electric field. Our results show an increased carrier separation with increasing QW thickness.